★ FOOD · BAKING · REFERENCE TABLE
A 9-inch round holds 8.0 cups and a 9 × 13 holds 14.0 — scale any recipe by ×1.75. This chart gives the usable batter capacity of all 12 common pans, from the 6-inch round’s 3.5 cups to the bundt’s 12.0, plus a live converter that scales your recipe and tells you the bake-time change. Capacities are Wilton’s, already allowing for the usual two-thirds fill.
The conversion is one division: the target pan’s capacity divided by the recipe pan’s capacity. A 9-inch round holds 8.0 cups and a 9 × 13 holds 14.0 cups, so the scale is ×1.75 and 8.00 cups of batter become 14.00 cups. Both pans are 2 inches deep, so the bake time stays the same. Pick your pans below and the converter does the rest.
Every pan has a usable batter capacity in cups, and the conversion is one division. A 9-inch round holds 8.0 cups and a 9 × 13 rectangle holds 14.0 cups, so the scale factor is 14.0 divided by 8.0, which is ×1.75. Multiply the recipe’s batter by that factor: 8.00 cups times ×1.75 is 14.00 cups, which fills the 9 × 13 to 100.00% — exactly full. The same rule runs the other way: a 9 × 13 recipe of 14.0 cups into a 9-inch round is 8.0 divided by 14.0, which is ×0.57, so 14.0 cups become 8.00 cups. The capacities already allow for the usual one-half to two-thirds fill, so do not apply a second reduction — the numbers in the table are the batter the pan takes, not the volume of the empty pan.
Setup: recipe pan 9-inch round (8.0 cups), target pan 9 × 13 rectangle (14.0 cups), recipe batter 8.00 cups.
Line 1 — scale factor. 14.0 / 8.0 = ×1.75.
Line 2 — batter needed. 8.00 × 1.75 = 14.00 cups.
Line 3 — target filled. 14.00 / 14.0 × 100 = 100.00%.
Line 4 — depth check. Both pans are 2 inches deep, so the bake time is the same — check 5 minutes early.
Line 5 — the verdict. Multiply every ingredient by ×1.75 and bake in the 9 × 13 for the same time as the round.
Capacities are usable batter in cups, from Wilton’s pan charts — already allowing for the usual one-half to two-thirds fill. Depth is the pan’s height in inches, which decides the bake time.
| Pan | Batter capacity | Depth | Notes |
|---|---|---|---|
| 6" round | 3.5 cups | 2.0″ | Half a 9-inch round recipe. |
| 8" round | 6.0 cups | 2.0″ | Three-quarters of a 9-inch round recipe. |
| 9" round | 8.0 cups | 2.0″ | The standard cake recipe size. |
| 10" round | 11.0 cups | 2.0″ | One and a third 9-inch round recipes. |
| 8" x 8" square | 8.0 cups | 2.0″ | Same batter as a 9-inch round. |
| 9" x 9" square | 10.0 cups | 2.0″ | One and a quarter 9-inch round recipes. |
| 9" x 13" rectangle | 14.0 cups | 2.0″ | Nearly two 9-inch round recipes. |
| 9" x 5" loaf | 8.0 cups | 2.5″ | Same batter as a 9-inch round, deeper. |
| 8" x 4" loaf | 4.0 cups | 2.5″ | Half a standard loaf recipe. |
| 10" bundt | 12.0 cups | 3.5″ | One and a half 9-inch round recipes. |
| 9" pie | 6.0 cups | 1.5″ | A shallow pan — bakes faster. |
| 12-cup muffin | 12.0 cups | 1.5″ | Twelve standard muffins, 1 cup of batter each in practice. |
8-inch round to 9-inch round: the 8-inch round holds 6.0 cups and the 9-inch round holds 8.0 cups, so the scale is 8.0 divided by 6.0, which is ×1.33. A 6.0-cup recipe becomes 8.00 cups, which fills the 9-inch round exactly. Both pans are 2 inches deep, so the time stays the same.
9 × 13 to 9-inch round: the scale is 8.0 divided by 14.0, which is ×0.57. A 14.0-cup recipe becomes 8.00 cups, which fills the 9-inch round exactly — and you keep 6.00 cups of batter back, enough for a few cupcakes.
9 × 5 loaf to 10-inch bundt: the loaf holds 8.0 cups and the bundt holds 12.0 cups, so the scale is 12.0 divided by 8.0, which is ×1.50. An 8.0-cup recipe becomes 12.00 cups. But the bundt is 3.5 inches deep against the loaf’s 2.5, so add 10–15 minutes to the bake time and test with a skewer.
10-inch round to 9 × 9 square: the 10-inch round holds 11.0 cups and the square holds 10.0 cups, so the scale is 10.0 divided by 11.0, which is ×0.91. An 11.0-cup recipe becomes 10.00 cups, which fills the square exactly.
Reverse — 10 cups of batter, three pans: in a 9 × 9 square (10.0 cups) it fills to 100.0% — exactly full. In an 8-inch round (6.0 cups) it is 166.7% full and overflows by 4.00 cups — do not bake it there. In a 9 × 13 (14.0 cups) it fills only 71.4%, so the layer is thin and bakes faster — check 5 minutes early.
The most common mistake is scaling by the pan’s width instead of its capacity. A 10-inch round is not a quarter bigger than an 8-inch round — it holds 11.0 cups against 6.0, which is nearly twice as much, because area grows with the square of the diameter. The second mistake is forgetting the depth: a 9 × 5 loaf and a 9-inch round both hold 8.0 cups, so the same batter fits either one — but the loaf is 2.5 inches deep against the round’s 2, so the loaf bakes slower. And the bundt is the trap: it holds 12.0 cups, the most of any pan here, but at 3.5 inches deep it needs the longest bake of all. Fit is about cups; time is about depth. See the recipe scaling calculator for scaling the ingredients once you know the factor, and the baking pan size chart for the pan dimensions behind these capacities.
The defaults are a full 9-inch round recipe — 8.00 cups of batter — scaled into a 9 × 13 rectangle. The capacities are Wilton’s usable batter figures, already allowing for the usual one-half to two-thirds fill: do not reduce them again. The bake-time rule is a rule of thumb, not a timer: same depth means the same time, check 5 minutes early; a pan at least half an inch deeper needs 10–15 minutes more; a pan at least half an inch shallower needs about 5 minutes less. Ovens vary, and a dark pan bakes faster than a light one, so always test with a toothpick or skewer. The muffin figure is for a standard 12-cup tin: 12.0 cups of batter makes twelve muffins, about a cup of batter per cup in practice once the cups are filled two-thirds.
Rounding convention, stated plainly: capacities are to one decimal in the table — 3.5, 6, 8, 11 — scale factors to two decimals — ×1.75, ×1.33 — batter needed to two decimals — 14.00 cups — and fill percentages to one decimal — 100.00%, 100.0%, 166.7%.
| Output | Formula | What it means |
|---|---|---|
| Scale factor | target capacity / recipe capacity | ×1.75 — 14 / 8. |
| Batter needed | recipe cups × scale | 14.00 cups — 8 × 1.75. |
| Target pan filled | batter needed / target capacity × 100 | 100.00% — the 9 × 13 is exactly full. |
| 8" round → 9" round | 8 / 6 | ×1.33 — 6 cups become 8.00 cups. |
| 9" x 13" → 9" round | 8 / 14 | ×0.57 — 14 cups become 8.00 cups. |
| 9" x 5" loaf → bundt | 12 / 8 | ×1.50 — 8 cups become 12.00 cups. |
| 10" round → 9" x 9" | 10 / 11 | ×0.91 — 11 cups become 10.00 cups. |
| 10 cups in a 9" x 9" | 10 / 10 × 100 | 100.0% full — exactly full. |
| 10 cups in an 8" round | 10 / 6 × 100 | 166.7% full — overflows by 4.00 cups. |
| 10 cups in a 9" x 13" | 10 / 14 × 100 | 71.4% full — a thin layer, bakes faster. |
The math is exact for the numbers you enter: the scale is the target capacity divided by the recipe capacity; the batter needed is the recipe cups times the scale; the fill is the batter needed divided by the target capacity, times 100. But the inputs carry the assumptions. The capacities are Wilton’s usable batter figures for standard pans: a pan from another maker, a pan with sloped sides, or a pan measured differently can hold a cup more or less. The fill rule is one-half to two-thirds, already built into the capacities — do not reduce them again, and do not fill past them. The bake-time rule is a rule of thumb: same depth means the same time, check 5 minutes early; deeper means 10–15 minutes more; shallower means about 5 minutes less. It does not account for oven hot spots, dark pans, glass pans, or high altitude — at altitude, see the high altitude baking calculator. It does not scale the leavening: baking powder and baking soda do not always scale linearly, and a recipe scaled by ×1.75 may need a little less leavening than the straight multiplication says. No studies or statistics are cited on this page beyond the Wilton capacities named above, because none are needed: every figure is arithmetic on the numbers you enter.
Bright Side Kit. "Baking Pan Conversion Chart: Cups, Sizes & Scaling" https://brightoolbox.com/baking-pan-conversion-chart/ Accessed October 24, 2026.8 cups of batter. That is the usable capacity — filled to the usual two-thirds, the way Wilton lists it. A 9 × 13 rectangle holds 14.0 cups, an 8-inch round holds 6.0 cups, and a 10-inch round holds 11.0 cups.
Divide the target pan’s capacity by the recipe pan’s capacity, then multiply every ingredient by that number. A 9-inch round (8 cups) to a 9 × 13 (14 cups) is 14 divided by 8, which is ×1.75 — so 8 cups of batter becomes 14.00 cups. Use the converter above and it does the division for you.
14.0 cups. That is the usable capacity of a 9 × 13 rectangle, and it is ×1.75 as much as a 9-inch round’s 8.0 cups. One standard 9-inch round recipe fills it only to 57.1%, so scale the recipe by ×1.75 to fill it.
Almost — two 9-inch rounds hold 16.0 cups and a 9 × 13 holds 14.0 cups. The 9 × 13 is 2.0 cups short, so a two-round recipe fills it to 114.3% — it overflows by 2.00 cups. Halve one round’s batter, or bake the full recipe and keep 2.00 cups back for cupcakes.
Only if the depth changes. Same depth means the same time — check 5 minutes early. A deeper pan, like the 3.5-inch bundt against a 2-inch round, needs 10–15 minutes more; a shallower pan, like the 1.5-inch pie, needs about 5 minutes less. The pan’s area decides how much batter fits; the depth decides how long it takes to bake through.
It will spill and burn on the oven floor. Ten cups of batter in an 8-inch round is 166.7% full — it overflows by 4.00 cups. The same 10 cups fills a 9 × 9 square to 100.0% and a 9 × 13 to only 71.4%. Never fill past the pan’s listed capacity: the capacities in the table already allow for the usual two-thirds fill.
Multiply by ×1.50 from a 9 × 5 loaf, or by ×1.50 from a 9-inch round. A 10-inch bundt holds 12.0 cups against the round’s 8.0, so an 8-cup recipe becomes 12.00 cups. And add 10–15 minutes to the bake time, because the bundt is 3.5 inches deep.
For batter — the usable capacity. The numbers come from Wilton’s pan charts, which list how much batter a pan takes when filled to the usual one-half to two-thirds. Do not add a second reduction: a 9-inch round takes 8.0 cups of batter, not 8.0 cups times two-thirds.